The Sinewave Indicator was created by John Ehlers (Cybernetic Analysis For Stocks And Futures pgs 154-155) and this is an updated version of his original Sinewave Indicator which in my opinion seems to be more reactive to changes. Buy when the blue line crosses over the red line and sell when the blue line crosses under the red line. Also keep in mind that this indicator is based on cycles so it won't act the same as a typical indicator.
Let me know if there are other scripts you would like to see me publish or if you want something custom done!